Automatic stapling device



May 17, 1966 .1. J. OUSSANI AUTOMATIC STAPLING DEVICE 2 Sheets-$heet x Filed April 8, 1964 FIG.

J K r /L May 17, 1966 J. J. OUSSANI AUTOMATIC STAPLING DEVICE 2 Sheets-Sheet 2 Filed April 8, 1964 INVENTOR. was: I aussa/v/ United States Patent 3,251,524 AUTOMATIC STAPLING DEVICE James J. Oussani, 777 5th Ave., Brooklyn 32, N.Y. Filed Apr. 8, 1964, Ser. No. 358,275 2 Claims. (Cl. 227-7 This invention relates to an electrical stapling device, and more particularly to a high speed stapler of the solenoid operated type.

- More particularly, this invention relates to a solenoid actuated stapler of the general type shown in my copending application Serial No. 142,917, filed October 4, 1961, now Patent No. 3,151,329, issued October 6, 1964, wherein the stapler is fired or actuated by the insertion of a workpiece, such as a stack of papers to be fastened together, into contact with a switch.

Still more particularly, this invention relates to an improved stapler device and switch of the type described.

It will be readily recognized that in automatic power actuated staplers, it is imperative that each time a workpiece is inserted into contact with the switch, only a single stapling cycle is performed. In my aforesaid pending application I have disclosed a novel switch device wherein the likelihood of accidental repeat operations is greatly reduced, without any substantial sacrifice in the speed with which the stapler is able to perform repeated fastener operations, where a workpiece is inserted, withdrawn and then reinserted. While the stapler device of the aforementioned pending application represents a considerable advance by permitting rapid operation, where desired, and a high degree of safeguard against accidental repeat operations, it has nonetheless been found that where a device in accordance with said application is subjected to hard and repeated usages, accidental repeat operations may occasionally occur.

While all of the causes of such occasional repeat operations have not been positively ascertained, I. have determined, after considerable research, that such operation typically may occur when the contact closer latch fails positively to engage with the moving contact of my prior device. In such prior device a resilient contact having an aperture is positioned in front of a latch member. The latch includes a shoulder which passes through the aperture and normally engages against the front face of the contact so that when the latch is carriedv rearwardly by insertion of a workpiece, the contact is carried with it. Spring means are provided in my said device to depress the latch into contact engaging positions.

After hard usage, I have discovered that the shoulder surface may become worn and alsothe under surface of the latch may develop unevenness. When these conditions develop, the resilient contact may not be. positively engaged by the latch shoulder but, instead, maybe eng'aged by the worn or uneven portions above noted. The spring urges these portions against the upper edge of the resilient contact and, hence, where the worn or uneven portions are pressed against the resilient contact and the latch moved rearwardly, the resilient contact will be carried rearwardly, not by the shoulder but, rather, by the worn or uneven portions. When'thi s condition occurs, the contacts may be momentarily closed and prematurely released, since such engagement of the contact does not afford the positive linkage to the latch which is provided by the shoulder. Under such circumstances, the solenoid may fire without driving the stapler through an entire driving stroke. Also, since the range of rearward movement of the latch must be greater than needed to close the contacts, it is possible for the contacts to close, spring forward and become re-engaged withthe latch, all during a single rearward movement. Under such circumstances, the contact may again be carried rearwardly to closed position by such further portions of the latch,.resulting in a refiring.

I have discovered that in large measure the erosive effects responsible for the wear on the latch shoulder and unevenness on the under surface of the latch of my prior device is due to the forwardly springing snap action of the resilient contact of my said device, resulting in a scraping against the shoulderand under surface of the latch each time the latch is pivoted upwardly to clear the resilient contact by the downward force of the stapler.

As will be more fully set forth, I have obviated the effects above noted in the device to be described by disposing the contacts behind the arm for closing the contacts, by eliminating the use of a pulling latch shoulder for closing the contacts, and by employing a burnishing stop which slidingly bears against the contact closer arm as the same shifts rearwardly to close the contacts. The burnishing stop acts continuously to smooth the upper surface of the arm, to counteract any scraping effects of the contact against the said upper surface, thus preventing the formation of irregularities on. such surface which might catch against the resilient contact and thus cause repeat operations.

Accordingly, it is an object of this invention to provide an automatic stapler device and switch which is susceptible of rapid repeat operations and in which a maximum safeguard against accidental contact closing is provided.

A further object of the invention is the provision of a simplified switch assembly more positive in its action, more economical to manufacture, and more durable than switch assemblies heretofore known.

A further object of this invention is to provide an improved stapler device with all of the advantages aforesaid, which may be actuated by the insertion of a relatively bendable, lightweight workpiece, without fear of jamming or misactuation of the device.

A still further object of the invention is the provision of an improved automatic fastener device of the type actuated by the insertion of a workpiece, wherein there is substantially no likelihood of the workpiece becoming jammed, or in failing to fire the stapler assembly, notwithstanding such workpiece may consist only of a few hereof, in which- FIGURE-l is a side elevati-onal view of a stapler device in accordance with the invention, with parts being broken away to show details of construction;

FIGURE 2 is a magnified fragmentary section taken on the line 22 of FIGURE 1;

FIGURE 3 is a vertical section similar to FIGURE 2, with the parts shown as positioned after the driving of a staple;

FIGURE 4 is a section taken on the line 44 of FIG- URE 3, showing the position of the parts of the switch mechanism when the stapling device has been driven through an operative cycle, and with the stapler at its low point of travel;

FIGURE 5 is a sectional view similar to FIGURE 4, showing the position of the parts after the completion of a stapling cycle, with the actuating mechanism and stapler returned to their initial raised position but before withdrawal of the workpiece;

FIGURE 6 is a sectional view taken on the line 66 of FIGURE 3.

In accordance with the invention shown in FIGURE 1, the stapler apparatus includes a housing 10 having a base 11 which has depending suction cup feet 12 extending beneath the base. A conventional stapler device 13 is fixedly mounted on the base 11 by any suitable means, such as screws 14.

Mounted within the housing 19, on side wall 15, is a solenoid assembly 16 including a plunger 17 disposed over a portion of the stapler device 13. A spring 13 maintains the plunger'normally in raised position, it being understood that energizing the coil of the solenoid assembly 16 causes the plunger to become depressed and thereby drive stapler 13. Carried on the stapler 13 is an offset rail portion 19, for purposes which will become apparent from the ensuing description.

The circuit through the coil of the solenoid assembly 16 is controlled by a switch mechanism 20, which mechanism is adjustably mounted within the limits of longitudinal slot 21 by a clamp knob 22 which is threaded into a bolt member 23 carried on the switch assembly 20, it being understood that tightening of the knob 22 sandwiches the side wall portions 24 defining the slot 21 between the knob 22 and the switch assembly.

The base 11'is provided with a forwardly and rearwardly extending groove or slot 25, which slot is coextensive with the range of adjustment of the switch assembly on the housing, as provided by the slot 21.

The mechanism of. the switch assembly 20 will next be described. The assembly 20 includes a switch housing 3! having a horizontally disposed trunnion 31 fixed thereto. To the trunnion 31 there is pivotally connected trip lever 32, for swinging movement in a vertical plane. The trip lever, at its lower end, includes an abutment finger 33, lower portions of which extend into the longitudinally disposed groove 25. Preferably, the transverse dimension of the finger 33 and groove are such that relatively small clearances are providedbetween the last mentioned members.

It will be readily recognized that instead of the groove 25 being recessed in the base, the groove may be supplanted by a slot which extends entirely through the base.

The trip lever 32 is urged forwardly or toward the front of the stapler by a coil spring 34, tensioned between the lever and a portion of the housing 30. A contact closer arm 35 is pivotally mounted to lever 32 on a horizontally disposed pivot member 36, made fast to the trip lever 32. The contact closer arm 35 includes a forward branch 37 and a rearward branch 38, a coil spring 39 being tensioned to the lever 32 and the forward arm 37 to cause the arm to be urged clockwise, when viewed as shown in FIGURE 6.

The closer arm 35 is preferably formed of insulating material, an upper surface 40 of said arm being normally positioned against a burnishing stop portion 41 which.

may be formed integrally with the switch housing 39 and which tends to restrain the clockwise movement of the arm 35 under the influence of spring 39. Also, as the lever is shifted rearwardly, the upper surface 40 will wipe against the iburnishing stop 41, against which it is urged by spring 39. The lever 32 is afforded a relatively limited range of forward and rearward movement by the inturned lug members 45, 46, which act as limit stops for the lever.

Directly behind the rearmost end 47 of the contact closer arm 35, in the normal position of said arm as shown in FIGURE 6, there are disposed a pair of normally spaced-apart contacts 48, 49, the contacts in the spaced-apart position shown in FIGURE 6 being insulated from each other. A portion of the forward contact 49, adjacent its lower edge 49a, is disposed directly behind and in potential direct contact with the rear end 47 of the closer arm 35. The contact 49, which is preferably formed of a strip of resilient metal, is so shaped as to be disposed clear of the contact 48 but may be pressed against its own resilience into engagement with the contact 48 when the rear portion 47 of the closer arm 35 is moved rearwardly. It will be evident that when the said rear portion 47 is shifted clear of the contact 49,

4 the contact will, in turn, spring clear of engagement with the contact 43.

A deactivator slide 50 is vertically shiftalbly mounted to the switch housing 30, the slide being provided with spaced slots 51, 51, within which are disposed spaced retainer limit pins 52, '52 carried by the switch housing 30.

A vertically disposed tension spring 53, biased between the slide 50 and a pin 52, serves to maintain .the slide in a normally upward position. The lower portion of the slide includes an offset portion 54 which overlies the upper surface 40 of the rear branch of the closer arm 35. Connected to the offset portion 54 there is formed an inwardly directed, generally L-shaped abutment portion 55 which underlies the rail portion 19 made fast to the stapler 13.

It will be understood that as the stapler is driven through an operative cycle by the plunger 17, the rail 19 is driven downwardly, carrying with it the L-shaped portion 55, and hence the offset portion 54 which overlies the rearward arm 38 of the contact closer arm 35.

The operation of the device will be readily understood from the foregoing.

The parts are shown in FIGURE 6 ready to receive a workpiece comprising sheets of paper or the like to be attached together. The workpiece, when inserted, will engage against the abutment finger 33, and will carry the finger and lever 32 to the left as viewed in FIGURE 6, and to the right as viewed in FIGURE 5. As the lever 32 is shifted to the left, as viewed in FIGURE 6, against the tension of the spring 34, the rear portion 47 engages against the contact 94 adjacent the lower end 49a, carrying the contact rearwardly into engagement with the contact48. When the contacts 48 and 49 are thus engaged, a circuit through the coils of solenoid assembly 16 is completed and the plunger 17 is rapidly urged downwardly against the stapler .13, causing a staple to be driven into the workpiece.

It will be understood that the position of a staple in the workpiece will be regulated by the adjustment of the switch assembly 20 within the slot 21 formed in the housing 10.

It will also be under-stood that the contacts 48, 49 remain in engagement under the rearward pressing infiuence of the end 47 of the switch closer arm 35 until the rearward branch 38 of the said closer arm is depressed by the oflfset portion 54 of the slide 50, in the manner previously set forth. As the end'portion 47 is depressed to a level beneath the lower edge 49a of the contact 49 (see FIGURE 4), the contact 49 will spring forwardly to the position as shown in said figure. While there may be more slight scraping of the lower edge of the contact 39 against the upper edge 40 of said arm 35 in the course of releasing the contact, the formation of irregularities of any appreciable size on such part is prevented by the wiping of the parts 40 and 41 in the course of closing the contact. When .the contacts open, current flow through the solenoid will cease and the plunger will be lifted by spring 18, permitting the stapler carrying rail 19 to return to its normally raised position. When the rail 19 is raised clear of the L-shaped portion 55 of the slide 50, the slide will be lifted from the position of FIGURE 4 to the position of FIGURE 5, under the influence of spring 53, clear of contact with the contact closer arm 35. The rear end 47 of the closer arm 35 will not be permitted to return to its normal position as shown in FIGURE 6, however, under the influence of spring 39 by reason of the engagement of the under edge 49a of the contact 49 against the upper surface of the closer arm 35.

It will be understood that the end 47 cannot be returned to a position at which it can actuate contact 49 until the lever arm 32 is permitted to shift forwardly to the position shown in FIGURE 6. Such forward shifting is, in turn, blocked by the workpiece W and the initial orientation of the parts can be achieved only by a withdrawal of the workpiece W. It will thus be seen that until the said workpiece has been withdrawn, to permit end 47 to return to a potentially direct contact position adjacent contact 49, no repeat operation of the device may be achieved.

A further feature of the invention lies in the provision of depending finger 33 riding in the groove 25, with relatively close clearance between these parts. In my prior mentioned structure, the comparable part to the abutment finger was pivotally mounted to the part comparable to lever 32 and was permitted to ride against the base portion. I have discovered that after substantial use, particularly where the switch remains in a given position in its adjustment slot, and in certain cases without substantial use, the insertion of a few relatively flexible sheets of paper will not, in all instances, properly trigger the stapler mechanism. 1 have determined that the occasional failures of such mechanism were due to the tendency of the few sheets to pass beneath the abutment finger, with the result that no tripping action would be effected or that the staple would not be accurately positioned with respect to the leading edge of the workpiece. This latter reaction was found to occur particularly where a portion of the workpiece passed beneath the abutment and other portions of the workpiece engaged against the abutment, to effect the circuit closing movement. By providing an abutment which extends into a groove formed in the base, or, alternatively, entirely through a slot formed in the base, the problem of working with thin workpieces has been eliminated.

It will be noted that the switch mechanism of the present invention is simplified and more rugged than the switch mechanisms heretofore known and incorporates fewer parts than such known mechanisms, while still possessing all the advantages set forth above.

Having thus described the invention and illustrated its use, what is claimed as new and is desired to be secured by Letters Patent is:

1. In an electrical fastening device including electrical motor means and a fastener member positioned to be actuated by said motor means, a switch assembly for actuation by a workpiece comprising a switch housing, a horizontally disposed trunnion member mounted on said housing, a generally vertically depending trip lever pivotally mounted on said trunnion, said trip lever including an abutment finger positioned to be engaged by a workpiece inserted into said fastening device, spring means urging said lever to a first forward position, a pair of contacts spring biased into spaced-apart circuit breaking position carried on said housing and disposed behind said lever, one said contact being disposed in front of the other, a contact closer arm mounted to said lever for pivotal movement in a vertical plane, said arm including a rear portion disposed forwardly of and in potential direct contact with said one of said contacts, said arm including an upper portion normally disposed in a plane slightly above the level of the lowermost edge of said one of said contacts, second spring means interposed between said lever and said arm for upwardly biasing said rear portion of said arm, burnishing stop means on said switch housing.

engaging said upper portion under the biasing influence of said second spring means thereby to locate said rear portion at a desired height with respect to said one of said contacts, said stop means wipingly engaging the upper surface of said closer arm during rearward movement thereof, and trip means carried by said housing and actuated by operation of said fastener device for depressing said rear portion and portions of the upper edge of said arm to a level below the lower edge of saidforward contact, whereby when said lever is shifted rearwardly by insertion of a workpiece and said trip means is operated by said fastener, said forward contact will spring forwardiy and the lower edge of said contact will lie against the upper edge of said rearwardly shifted trip arm.

2. An electrical fastening device having a horizontal bse portion, electrical motor means carried by said device, a fastener member positioned on said base portion to be actuated by said motor means, a switch assembly for actuation by rearward insertion of a workpiece comprising a switch housing, a horizontally disposed trunnion member mounted on said housing, a trip lever pivotally mounted on said trunnion for swinging movement in a vertical plane, a depending abutment finger integrally formed with said trip lever, a longitudinally extending groove formed in said base portion beneath the horizontal upper surface of said base portion, said finger of said lever riding within said groove, the transverse extent of said groove being slightly in excess of the transverse extent of said finger, spring means biased between said housing and said lever urging said lever to a first forward position, a pair of contacts mounted on said housing normally spring biased into spaced-apart circuit breaking position, one said contact being disposed in front of the other, a contact closer arm of insulating material mounted to said lever for pivotal movement in a vertical plane, said arm including front and rear branches, respectively, forwardly and rearwardly of the pivotal connection of said arm and lever, tension spring means interposed between said forward arm and said lever'to impart an upward force to said rear arm, burnishing stop means on said housing biased into wiping engagement with the upper surface of said rear arm under the influence of said tension spring means, said stop means being positioned to locate the rear portion of said rear arm adjacent and in potential direct contact with the front surface of said one of said contacts, said upper portion of said rear arm being normally disposed in a plane slightly above the level of the lowermost edge of said one of said contacts, trip means carried by said housing and actuated by operation of said fastener device for depress.-

ing said rear arm by engagement with said upper edge to dispose said upper edge and rear portion beneath the level of the lower edge of said one of said contacts, whereby when said lever is shifted rearwardly by insertion of a workpiece to close said contacts and said trip means is operated by said fastener, said forward contact will spring forwardly and the lower edge of said contact will lie References Cited by the Examiner UNITED STATES PATENTS 6/1940 Oussani 227-7 3/1961 Oussani 227-7 GRANVILLE Y. CUSTER, JR., Primary Examiner. 

1. IN AN ELECTRICAL FASTENING DEVICE INCLUDING ELECTRICAL MOTOR MEANS AND A FASTENER MEMBER POSITIONED TO BE ACTUATED BY SAID MOTOR MEANS, A SWITCH ASSEMBLY FOR ACTUATION BY A WORKPIECE COMPRISING A SWITCH HOUSING, A HORIZONTALLY DISPOSED TRUNNION MEMBER MOUNTED ON SAID HOUSING, A GENERALLY VERTICALLY DEPENDING TRIP LEVER PIVOTALLY MOUNTED ON SAID TRUNNION, SAID TRIP LEVER INCLUDING AN ABUTMENT FINGER POSITIONED TO BE ENGAGED BY A WORKPIECE INSERTED INTO SAID FASTENING DEVICE, SPRING MEANS URGING SAID LEVER TO A FIRST FORWARD POSITION, A PAIR OF CONTACTS SPRING BIASED INTO SPACED-APART CIRCUIT BREAKING POSITION CARRIED ON SAID HOUSING AND DISPOSED BEHIND SAID LEVER, ONE SAID CONTACT BEING DISPOSED IN FRONT OF THE OTHER, A CONTACT CLOSER ARM MOUNTED TO SAID LEVER FOR PIVOTAL MOVEMENT IN A VERTICAL PLANE, SAID ARM INCLUDING A REAR PORTION DISPOSED FORWARDLY OF AND IN POTENTIAL DIRECT CONTACT WITH SAID ONE OF SAID CONTACTS, SAID ARM INCLUDING AN UPPER PORTION NORMALLY DISPOSED IN A PLANE SLIGHTLY ABOVE THE LEVEL OF THE LOWERMOST EDGE OF SAID ONE OF SAID CONTACTS, SECOND SPRING MEANS INTERPOSED BETWEEN SAID LEVER AND SAID ARM FOR UPWARDLY BIASING SAID REAR PORTION OF SAID ARM, BURNISHING STOP MEANS ON SAID SWITCH HOUSING ENGAGING SAID UPPER PORTION UNDER THE BIASING INFLUENCE OF SAID SECOND SPRING MEANS THEREBY TO LOCATE SAID REAR PORTION AT A DESIRED HEIGHT WITH RESPECT TO SAID ONE OF SAID 